Immediately after reheating, most SM interactions are still too slow to compete with the Hubble expansion.
In addition to the SM gauge interactions, the only process in thermal equilibrium is the top-quark Yukawa interaction.
As a consequence, a large number of global charges remains conserved in the thermal bath.
Indeed, given that the SM particle content can be described by 16 chemical potentials (15 fermion representations, see Tab. REF , plus the SM Higgs doublet \(\Phi \) ), one Yukawa interaction in equilibrium means that one is able to define 15 linearly independent global charges.
One possible choice is, e.g., [1]}
\(\left\lbrace \eta _u,\: \eta _B,\: \eta _{d-b},\: \eta _\tau ,\: \eta _{u-c},\: \eta _\mu ,\: \eta _{B_1-B_2},\: \eta _{d-s},\: \eta _{u-d},\: \eta _{2B_1-B_2-B_3},\: \eta _e,\:\eta _{\Delta _e},\:\eta _{\Delta _\mu },\:\eta _{\Delta _\tau },\:\eta _Y\right\rbrace  \,,\) 
